The present invention relates generally to elastic composites. More particularly, the present invention relates to an elastic composite that can be used in the manufacture of a garment, other textile or fabric structures, similar material structures, and the like, but more particularly, disposable absorbent articles and garments. The elastic composite of the present invention is well suited in providing an elastic component that can be employed in one or more areas of the disposable absorbent article. The present invention also relates to a system and method of making the elastic. The elastic composite and the system and method for making the elastic composite are particularly suited for use with or on disposable absorbent garments or articles such as baby diapers and training pants. To illustrate various aspects of the invention, exemplary and preferred embodiments are described herein in the context of disposable absorbent garments.
U.S. Pat. Nos. 7,462,172 and 7,361,246 provide background information on elastic composites (and the manufacture of such composites) of the type relevant to the present invention. Accordingly, some portions of the publications have been included herein to facilitate description of the invention. In any event, these two publications are also hereby incorporated by reference and made a part of the present disclosure, but only to the extent that incorporated subject matter provides background information and/or exemplary composites and processes suitable for use on, or with, the present inventive composites, systems, and methods. Thus, the incorporated subject matter shall not serve to limit the scope of the present invention.
Disposable absorbent garments contemplated by the invention include disposable diapers, disposable pull-on garments and training pants, and the like. These garments are worn about the lower torso or waist of the user so as to receive and contain urine and other bodily wastes. The benefits provided by the use of a disposable diaper on an infant are well known and its use has become widespread. Disposable pull-on garments include training pants, pull-on diapers, disposable underwear, and adult incontinence garments. As for training pants, these garments are used by young children to facilitate a child's transition from using diapers to wearing regular underpants (i.e., during toilet training). Training pants (and other disposable pull-on pants have closed sides such that the user or caregiver raises the garment about the user's legs to wear the garment and slips the garment downward about the user's legs to take it off.
The principal elements of a typical disposable absorbent garment include a liquid permeable inner layer (or topsheet), a liquid impermeable outer layer (or backsheet), and an absorbent core sandwiched between the inner and outer layers. Elastic members may be incorporated into different parts of the garment. For example, elastic members may be positioned longitudinally along a diaper, generally outboard of the absorbent core to effect a seal around the buttocks, legs, or both of the users. In addition, several elastic members (e.g., in the form of elongated elastic threads or strands) may be positioned laterally throughout the waist regions (including the side waist regions) of a disposable absorbent garment. The resulting elastication allows the garment to stretch when it is put on and when it is worn. The elastication allows the garment to accommodate variations in waist size and leg size of the user, while fitting snugly about the waist and legs.
When elastic members are incorporated into a part or area of the garment, that part or area typically becomes a distinct, functional component of the garment. These elastic components include the side panels or ear portions, the waistband, and fastening tabs. The elastic components to which the present invention is directed are generally elongated, and may be a distinct portion of a larger, unitary piece, or a separate, attachable component. Furthermore, the elastic component typically contains one or more sections or layers in addition to the elastic members. In this regard, such an elastic component may be referred to as an elastic composite of the type which the present invention is concerned.
Due in part to its multi-component construction, these elastic composites may require a dedicated sub-process for manufacture which must be accommodated by the greater garment manufacturing process. Alternatively, the elastic composite may be manufactured independently or simply, manufactured in a separate sub-process detached from the central garment manufacturing system. In either case, a source of the elastic composite may be provided as input to the garment manufacturing process.
In most applications, the elastic composite has a significant impact on the fit and sealability of the garment, as well as the general appearance and construction quality of the garment. The design and construction of the elastic composite can also represent a significant portion of the cost of manufacturing the garment. It is, therefore, always desirable to provide a functionally and/or aesthetically improved elastic composite or a cost effective system and method of making the elastic composite.
It is contemplated that, in some applications, manufacturing elastic composite having dual elasticized regions may prove more efficient and economical than producing elastic composites having a single elasticized region (even when single elasticized elastic composites are ultimately employed). In one respect, the present invention addresses the particular technical challenge of providing dual (or multiple) elasticized regions on an elastic composite. In another respect, the invention addresses the technical challenge of providing a system and method that is practical, efficient, and cost effective. For example, the system and method should preferably utilize commonly available components and sub-processes.
In any event, it is desirable for the target elastic composite (having dual elasticized regions), system, and method of manufacturing to be practical, and provide functional or aesthetic attributes. It is also desirable that the design and construction of the elastic composite has a minimal, if not positive, impact on the efficiency of present systems and methods. The design and construction should also have a minimal, if not positive, impact on the overall manufacturing cost of the elastic composite or the final product.